Chemical processing utilizing hydrogen containing supplemental fuel for catalyst processing

ABSTRACT

A method for processing a chemical stream includes contacting a feed stream with a catalyst in a reactor portion of a reactor system that includes a reactor portion and a catalyst processing portion. The catalyst includes platinum, gallium, or both and contacting the feed stream with the catalyst causes a reaction which forms an effluent stream. The method includes separating the effluent stream from the catalyst, passing the catalyst to the catalyst processing portion, and processing the catalyst in the catalyst processing portion. Processing the catalyst includes passing the catalyst to a combustor, combusting a supplemental fuel in the combustor to heat the catalyst, treating the heated catalyst with an oxygen-containing gas to produce a reactivated catalyst, and passing the reactivated catalyst from the catalyst processing portion to the reactor portion. The supplemental fuel may include a molar ratio of hydrogen to other combustible fuels of at least 1:1.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Stage Entry under 35 U.S.C. § 371 ofInternational Patent Application No. PCT/US2019/039209, filed Jun. 26,2019, which claims the benefit of U.S. Provisional Patent ApplicationSer. No. 62/694,193, filed Jul. 5, 2018, both of which are herebyincorporated by reference in their entireties.

BACKGROUND Field

The present disclosure generally relates to chemical processing systemsand the operation thereof and, more specifically, to processes includingsupplemental fuel streams for processing catalysts.

Technical Background

Light olefins may be utilized as base materials to produce many types ofgoods and materials. For example, ethylene may be utilized tomanufacture polyethylene, ethylene chloride, or ethylene oxides. Suchproducts may be utilized in product packaging, construction, textiles,etc. Thus, there is an industry demand for light olefins, such asethylene, propylene, and butene.

Light olefins may be produced by different reaction processes dependingon the given chemical feed stream, such as a product stream from a crudeoil refining operation. Many light olefins may be produced throughvarious catalytic processes, such as through catalytic dehydrogenationfor example, in which the feed stream is contacted with a fluidizedcatalyst that facilitates conversion of the feed stream into the lightolefins.

BRIEF SUMMARY

Many reaction processes for producing light olefins are endothermic andrequire heat input into the system to propagate the catalytic reactions.Coke deposits on the catalyst may be combusted during catalystregeneration, but the heat provided by combustion of coke deposits maynot be sufficient to propagate the endothermic reactions. Supplementalfuels may be introduced during catalyst regeneration to increase theheat input into the reaction system.

There is a continued need for improved processes for reactor systems forprocessing chemical streams to produce light olefins or other chemicalproducts, the processes including improved supplemental fuel sources forheating the catalyst. Many reactor systems for processing chemicalstreams to produce light olefins and other chemicals utilize relativelyhot catalyst, such as those catalysts heated to temperatures greaterthan 350° C. The catalyst may be circulated through fluidized reactorsystems, such as through a reactor portion (where chemical products aremade) and through a catalyst processing portion (where the catalyst isprocessed, such as but not limited to removal of coke, heating of thecatalyst, reactivating the catalyst, other catalyst processingoperations, or combinations of these).

In endothermic fluidized reactor systems, the reactor system may includea heat source to drive the process. For example, in fluidized catalyticcracking (“FCC”) reactions, coke generated by the reaction and depositedon the catalyst may be combusted in a combustor of the catalystprocessing portion to provide a major portion of the heat to drive thereaction process. As another non-limiting example, in fluidizedcatalytic dehydrogenation (FCDh) reactions, a supplemental fuel may beadded to the combustor to provide additional heat for the endothermicreaction along with combustion of a relatively small amount of cokegenerated from the dehydrogenation reaction. Supplemental fuels mayinclude significant proportions of methane and/or other hydrocarbons dueto the relatively inexpensive cost of methane and its energy efficiencyat relatively high temperatures, such as those of the catalyst duringoperation of the reactor system (e.g., temperatures above 650° C.).However, combustion of supplemental fuels that include mainly methaneand other hydrocarbons (e.g., greater than or equal to 50 mol % methaneand other hydrocarbons) during catalyst processing may lead to reducedactivity of the catalyst, such as a catalyst that includes platinum,gallium, or both for example.

The reduced activity of the catalysts can decrease the conversion thatcan be attained by the catalyst. In some fluidized reactor systems thatutilize supplemental fuels that include mainly methane and otherhydrocarbons, productivity of the reactor system may be maintained byincreasing the amount of the catalyst in the reactor system orincreasing the amount of active metal, such as platinum, gallium, orboth, in the catalyst. However, increasing the amount of active metal,such as platinum, gallium, or both, in the reactor system can increasethe operating costs of the reactor system.

Therefore, there is an ongoing need for reactor systems and processesthat increase the conversion of a chemical feed by reducing deactivationof the catalyst. In particular, there is an ongoing need for reactorsystems and methods that include combusting supplemental fuels thatreduce the extent of deactivation of the catalysts during combustion ofthe supplemental fuel, thereby increasing catalyst activity. The presentdisclosure, according to one or more embodiments, is directed toprocesses and reactor systems that include combusting a supplementalfuel having a relatively high concentration of hydrogen (e.g., molarratio of hydrogen to other combustible fuels of at least 1:1) in thecombustor of a catalyst processing portion of the reactor system to heatthe catalyst. Following combustion, the catalyst may be subjected to anoxygen treatment that includes exposing the catalyst to anoxygen-containing gas for a time sufficient to reactive the catalyst.

It was surprisingly and unexpectedly found that combusting asupplemental fuel having a relatively high concentration of hydrogen canresult in greater catalyst activity and an increase in the conversion ofthe reactor system compared to the conventional case of combusting asupplemental fuel that includes relatively high amounts of hydrocarbons(e.g., methane) under the same operating conditions (including the sameoxygen treatment following combustion). Additionally, combustion ofsupplemental fuels that include relatively high concentrations ofhydrogen can result in a catalyst with longer catalyst lifetime and mayenable a target conversion to be achieved with less bulk inventory ofcatalyst in the reactor system compared to the bulk inventory needed toachieve the same target conversion when the supplemental fuel is mainlyhydrocarbons (e.g., >50 mol % hydrocarbons). In some embodiments,combusting a supplemental fuel having a high concentration of hydrogenmay enable the reactor system to be operated with less active metal,such as platinum, gallium, or both, on the catalyst.

According to one or more aspects of the present disclosure, a method forprocessing a chemical stream may include contacting a feed stream with acatalyst in a reactor portion of a reactor system. The reactor systemmay include a reactor portion and a catalyst processing portion, and thecatalyst may include platinum, gallium, or both. The contacting of thefeed stream with the catalyst causes a reaction which forms an effluentstream comprising at least one product. The method may further includeseparating at least a portion of the effluent stream from the catalyst,passing the catalyst to the catalyst processing portion of the reactorsystem, and processing the catalyst in the catalyst processing portionof the reactor system. Processing the catalyst may include passing thecatalyst to a combustor of the catalyst processing portion, combusting asupplemental fuel in the combustor in the presence of the catalyst toproduce a heated catalyst, treating the heated catalyst with anoxygen-containing gas (oxygen treatment) to produce a reactivatedcatalyst, and passing the reactivated catalyst from the catalystprocessing portion to the reactor portion. The supplemental fuel mayinclude hydrogen and other combustible fuels, and a molar ratio ofhydrogen to the other combustible fuels in the supplemental fuel is atleast 1:1.

According to one or more other aspects of the present disclosure, amethod for dehydrogenating a hydrocarbon to produce one or more olefinsmay include contacting the hydrocarbon feed stream with a catalyst in areactor portion of a reactor system. The reactor system may include areactor portion and a catalyst processing portion, and the catalyst mayinclude platinum, gallium, or both. The contacting of the feed streamwith the catalyst may cause a reaction which forms an effluent streamcomprising at least one product. The method may further includeseparating at least a portion of the effluent stream from the catalyst,passing the catalyst to the catalyst processing portion of the reactorsystem, and processing the catalyst in the catalyst processing portionof the reactor system. Processing the catalyst may include passing thecatalyst to a combustor of the catalyst processing portion, introducinga supplemental fuel to the combustor, combusting the supplemental fuelin the combustor in the presence of the catalyst, subjecting a heatedcatalyst to an oxygen treatment to produce a reactivated catalyst, andpassing the reactivated catalyst from the catalyst processing portion tothe reactor portion. The supplemental fuel stream may include hydrogenand at least one hydrocarbon, and a molar ratio of hydrogen to othercombustible fuels in the supplemental fuel is at least 1:1.

It is to be understood that both the foregoing brief summary and thefollowing detailed description present embodiments of the technology,and are intended to provide an overview or framework for understandingthe nature and character of the technology as it is claimed. Theaccompanying drawings are included to provide a further understanding ofthe technology, and are incorporated into and constitute a part of thisspecification. The drawings illustrate various embodiments and, togetherwith the description, serve to explain the principles and operations ofthe technology. Additionally, the drawings and descriptions are meant tobe merely illustrative, and are not intended to limit the scope of theclaims in any manner.

Additional features and advantages of the technology disclosed hereinwill be set forth in the detailed description which follows, and in partwill be readily apparent to those skilled in the art from thatdescription or recognized by practicing the technology as describedherein, including the detailed description which follows, the claims, aswell as the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed description of specific embodiments of thepresent disclosure can be best understood when read in conjunction withthe following drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1 schematically depicts a reactor system, according to one or moreembodiments described herein;

FIG. 2 schematically depicts a reactor system flow chart, according toone or more embodiments described herein;

FIG. 3 schematically depicts another reactor system flow chart,according to one or more embodiments described herein;

FIG. 4 schematically depicts yet another reactor system flow chart,according to one or more embodiments described herein;

FIG. 5 schematically depicts a graph of propane conversion (y-axis) fora fluidized catalytic dehydrogenation reactor system as a function ofhydrogen composition (x-axis) of a supplemental fuel introduced to acombustor of the fluidized catalytic dehydrogenation reactor system,according to one or more embodiments described herein; and

FIG. 6 schematically depicts a graph of propane conversion (y-axis left)and propylene selectivity (y-axis right) for a fluidized catalyticdehydrogenation reactor system as a function of hydrogen composition(x-axis) of a supplemental fuel introduced to a combustor of the reactorsystem, according to one or more embodiments described herein.

It should be understood that the drawings are schematic in nature, anddo not include some components of a reactor system commonly employed inthe art, such as, without limitation, temperature transmitters, pressuretransmitters, flow meters, pumps, valves, and the like. It would beknown that these components are within the spirit and scope of thepresent embodiments disclosed. However, operational components, such asthose described in the present disclosure, may be added to theembodiments described in this disclosure.

Reference will now be made in greater detail to various embodiments,some embodiments of which are illustrated in the accompanying drawings.Whenever possible, the same reference numerals will be used throughoutthe drawings to refer to the same or similar parts.

DETAILED DESCRIPTION

Several embodiments of the present disclosure are discussed in thedetailed description which follows. One or more embodiments of thepresent disclosure are directed to methods for processing chemicalstreams in reactor systems utilizing a supplemental fuel to heat acatalyst. In particular, one or more embodiments of the presentdisclosure are directed to methods for processing chemical streams inwhich a supplemental fuel that includes hydrogen is combusted in acatalyst processing portion of the reactor system to heat the catalyst.For example, in some embodiments, the method for processing a chemicalstream may include contacting a feed stream with a catalyst in a reactorportion of a reactor system that includes a reactor portion and acatalyst processing portion. The catalyst may include platinum, gallium,or both. Contacting of the feed stream with the catalyst may cause areaction which forms an effluent stream that contains at least oneproduct, such as an olefin product for example. The method may includeseparating at least a portion of the effluent stream from the catalystand passing the catalyst to the catalyst processing portion of thereactor system. The method may further include processing the catalystin the catalyst processing portion. Processing the catalyst may includepassing the catalyst to a combustor of the catalyst processing portionand combusting a supplemental fuel that includes a high-concentration ofhydrogen (molar ratio of hydrogen to other combustible fuels of at least1:1) in the combustor. Combusting the supplemental fuel that includes arelatively high concentration of hydrogen may increase the temperatureof the catalyst to produce a heated catalyst. Processing the catalystmay also include treating the heated catalyst with an oxygen-containinggas to produce a reactivated catalyst. The reactivated catalyst may bepassed back to the reactor portion of the reactor system.

Combustion of the supplemental fuel that includes a relatively highconcentration of hydrogen (e.g., molar ratio of hydrogen to othercombustible fuels of at least 1:1) to heat the catalyst during catalystprocessing was found to increase the conversion of reactants in thereactor system compared to combusting a supplemental fuel consistingmainly of methane or other hydrocarbons. This high activity may resultin increased catalyst lifetime in the reactor system and may enableincreasing the unit capacity of the reactor system. The higher catalystactivity may also enable the reactor system to operate with less activemetal, such as platinum, gallium, or both, in the reactor system (e.g.,less bulk inventory of catalyst or less active metal in the catalyst).

As used herein, the term “fluidized reactor system” refers to a reactorsystem in which one or more reactants are contacted with a catalyst in afluidization regime, such as bubbling regime, slug flow regime,turbulent regime, fast fluidization regime, pneumatic conveying regime,or combinations thereof in different portions of the system. Forexample, in a fluidized reactor system, a feed stream containing one ormore reactants may be contacted with the circulating catalyst at anoperating temperature to conduct a continuous reaction to produce theproduct stream.

As used herein, “continuous reaction” may refer to a chemical reactionconducted by feeding reactants, catalyst, or combinations thereof, andwithdrawing products from a reactor or reaction zone under steady stateconditions continuously over a time period, which is defined by acommencement of the reaction at the beginning of the time period and acessation of the reaction at the end of the time period. Thus, operationof the reactor systems described herein may include commencement of thereaction, continuous reaction, and cessation of the reaction.

As used herein, “deactivated catalyst” may refer to a catalyst havingdecreased catalytic activity resulting from buildup of coke and/or lossof catalyst active sites.

As used herein, “catalytic activity” or “catalyst activity” may refer tothe degree to which the catalyst is able to catalyze the reactionsconducted in the reactor system.

As used herein, “catalyst processing” may refer to preparing thecatalyst for re-introduction into the reactor portion of the reactorsystem and may include removing coke deposits from the catalyst, heatingthe catalyst, reactivating the catalyst, stripping one or more gasesfrom the catalyst, other processing operations, or any combinations ofthese.

As used herein, “processed catalyst” may refer to catalyst that has beenprocessed in the catalyst processing portion of the reactor system.

As used herein, “catalyst reactivation” or “reactivating the catalyst”may refer to processing the deactivated catalyst to restore at least aportion of the catalyst activity to produce a reactivated catalyst. Thedeactivated catalyst may be reactivated by, but not limited to,recovering catalyst acidity, oxidizing the catalyst, other reactivationprocess, or combinations thereof. In some embodiments, catalystreactivation may include treating the catalyst with an oxygen-containinggas for a period of greater than 2 minutes.

As used herein, “supplemental fuel” may refer to any fuel sourceintroduced to the catalyst processing portion of the reactor system tofacilitate removing coke from the catalyst and/or heating the catalyst.Supplemental fuel does not include coke deposited on the catalyst.

As previously discussed herein, according to one or more embodiments,the methods and processes disclosed herein may be utilized to conduct areaction in a reactor system for processing one or more chemicalstreams. In non-limiting examples, the reactor systems disclosed hereinmay be utilized to produce light olefins from hydrocarbon feed streamsthrough continuous reaction of the hydrocarbon feed streams. Forexample, in some embodiments, light olefins may be produced throughdehydrogenation of a hydrocarbon feed stream in the presence of acatalyst that includes platinum, gallium, or both in a fluidizedcatalytic dehydrogenation (FCDh) reactor system. While the processes andmethods for processing a chemical stream in a reactor system aredescribed herein in the context of hydrocarbon processing to form lightolefins through fluidized catalytic dehydrogenation, it should beunderstood that the processes and methods disclosed herein may beutilized with any reactor system that includes a catalyst having anactive metal, such as platinum, gallium, other active metal, orcombinations thereof, and that includes heating the catalyst bycombustion of a supplemental fuel. As such, the presently describedmethods and processes for processing a chemical stream in a reactorsystem should not be limited only to embodiments for reactor systemsdesigned to produce light olefins or alkyl aromatics through fluidizedcatalytic dehydrogenation, such as the reactor system in FIG. 1.

The reactor systems and methods for processing the chemical streams willnow be discussed in further detail. The chemical stream that isprocessed may be referred to as a feed stream, which is processed by areaction to form a product stream. The feed stream may comprise acomposition, and depending upon the feed stream composition, anappropriate catalyst may be utilized to convert the contents of the feedstream into a product stream that may include light olefins or otherchemical products. For example, a feed stream for an FCDh reactor systemmay comprise at least one of propane, n-butane, iso-butane, ethane, orethylbenzene. In the FCDh system, the feed stream may be converted tolight olefins or other products through dehydrogenation in the presenceof a dehydrogenation catalyst.

In some embodiments, the catalyst for conducting dehydrogenation in anFCDh reactor system may include a catalyst comprising platinum, gallium,or both. In some embodiments, the catalyst may further include one ormore other noble metals from Groups 9 and 10 of the IUPAC periodictable. For example, in some embodiments, the catalyst may include one ormore noble metals chosen from, palladium (Pd), rhenium (Rh), iridium(Jr), or combinations of these. In some embodiments, the catalyst mayalso include one or more metals chosen from indium (In), germanium (Ge),or combinations of these. The catalyst may also include a promotermetal, such as an alkali metal or an alkaline metal. In someembodiments, the promoter metal may be potassium. The metals of thecatalyst may be supported on a carrier. The carrier may include one ormore inorganic bulk metal oxides, such as silica, alumina,alumina-containing silica, zirconia (ZrO₂), titania (TiO₂), other metaloxides, or combinations of metal oxides. In some embodiments, thecarrier may include a microporous material, such as ZSM-5 zeolite. Thecatalytic metals, such as platinum, gallium, potassium, and/or othercatalytically active metals, may be supported on the surface of thecarrier or incorporated into the carrier. In some embodiments, thecatalyst may include platinum, gallium, and optionally potassiumsupported on an alumina-containing silica carrier.

Referring now to FIG. 1, an example reactor system 102 is schematicallydepicted. The reactor system 102 generally includes a reactor portion200 and a catalyst processing portion 300. As used herein in the contextof FIG. 1, the reactor portion 200 refers to the portion of a reactorsystem 102 in which the major process reaction takes place. For example,the reactor system 102 may be an FCDh system in which the feed stream isdehydrogenated in the presence of the dehydrogenation catalyst in thereactor portion 200 of the reactor system 102. The reactor portion 200comprises a reactor 202 which may include a downstream reactor section230, an upstream reactor section 250, and a catalyst separation section210, which serves to separate the catalyst from the chemical productsformed in the reactor 202.

Also, as used herein, the catalyst processing portion 300 of the systemof FIG. 1 generally refers to the portion of a reactor system 102 inwhich the catalyst is in some way processed, such as removal of cokedeposits, heating of the catalyst, reactivating the catalyst, otherprocessing operations, or combinations of these. In some embodiments,the catalyst processing portion 300 may include a combustor 350, a riser330, a catalyst separation section 310, and an oxygen treatment zone370. The combustor 350 of the catalyst processing portion 300 mayinclude one or more lower combustor inlet ports 352 and may be in fluidcommunication with the riser 330. The combustor 350 may be in fluidcommunication with the catalyst separation section 210 via standpipe426, which may supply deactivated catalyst from the reactor portion 200to the catalyst processing portion 300 for catalyst processing (e.g.,coke removal, heating, reactivating, etc.). The oxygen treatment zone370 may be in fluid communication with the upstream reactor section 250(e.g., via standpipe 424 and transport riser 430), which may supplyprocessed catalyst from the catalyst processing portion 300 back to thereactor portion 200. The combustor 350 may include the lower combustorinlet port 352 where air inlet 428 connects to the combustor 350. Theair inlet 428 may supply air or other reactive gases, such as anoxygen-containing gas to the combustor 350. Air and/or other reactivegases, may be introduced to the combustor 350 to aid in combustion ofthe supplemental fuel. The combustor 350 may also include a supplementalfuel inlet 354. The supplemental fuel inlet 354 may supply asupplemental fuel stream 356 to the combustor 350. The supplemental fuelstream 356 may include the supplemental fuel. The oxygen treatment zone370 may include an oxygen-containing gas inlet 372, which may supply anoxygen-containing gas to the oxygen treatment zone 370 for oxygentreatment of the catalyst.

Referring to FIG. 1, general operation of the reactor system 102 toconduct a continuous reaction will be described. During operation of thereactor portion 200 of the reactor system 102, the feed stream may enterthe transport riser 430, and the product stream may exit the reactorsystem 102 via pipe 420. According to one or more embodiments, thereactor system 102 may be operated by feeding a chemical feed (e.g., ina feed stream) and a fluidized catalyst into the upstream reactorsection 250. The chemical feed may contact the catalyst in the upstreamreactor section 250, and each may flow upwardly into and through thedownstream reactor section 230 to produce a chemical product. Thechemical product and the catalyst may be passed out of the downstreamreactor section 230 to a separation device 220 in the catalystseparation section 210. The catalyst may be separated from the chemicalproduct in the separation device 220. The chemical product may then betransported out of the catalyst separation section 210. For example, theseparated vapors may be removed from the reactor system 102 via a pipe420 at a gas outlet port 216 of the catalyst separation section 210.According to one or more embodiments, the separation device 220 may be acyclonic separation system, which may include two or more stages ofcyclonic separation.

According to some embodiments, following separation from vapors in theseparation device 220, the catalyst may generally move through thestripper 224 to the reactor catalyst outlet port 222 where the catalystmay be transferred out of the reactor portion 200 via standpipe 426 andinto the catalyst processing portion 300. Optionally, the catalyst mayalso be transferred directly back into the upstream reactor section 250via standpipe 422. In some embodiments, recycled catalyst from thestripper 224 may be premixed with processed catalyst from the catalystprocessing portion 300 in the transport riser 430.

The separated catalyst may be passed from the catalyst separationsection 210 to the combustor 350 of the catalyst processing portion 300.The catalyst may be processed in the catalyst processing portion 300 toremove coke deposits, heat the catalyst, reactivate the catalyst, othercatalyst processing, or any combinations of these. As previouslydiscussed, processing the catalyst in the catalyst processing portion300 may include removing coke deposits from the catalyst, raising thetemperature of the catalyst through combustion of a combustion fuelsource, reactivating the catalyst, stripping one or more constituentsfrom the catalyst, other processing operation, or combinations of these.In some embodiments, processing the catalyst in the processing portion300 may include combusting a combustion fuel source in the presence ofthe catalyst in the combustor 350 to remove coke deposits and/or heatthe catalyst to produce a heated catalyst. The heated catalyst may beseparated from the combustion gases in the catalyst separation portion310. In some embodiments, the heated catalyst may then be reactivated byconducting an oxygen treatment of the heated catalyst. The oxygentreatment may include exposing the catalyst to an oxygen-containing gasfor a period of time sufficient to reactivate the catalyst.

In some embodiments, the combustion fuel source may include coke orother contaminants deposited on the catalyst in the reactor portion 200of the reactor system 102. In some reaction systems, the catalyst may becoked following the reactions in the reactor portion 200, and the cokemay be removed from the catalyst by a combustion reaction in thecombustor 350. For example, oxidizer (such as air) may be fed into thecombustor 350 via the air inlet 428.

However, as previously discussed, in some reaction systems, the coke andother contaminants deposited on the catalyst may not be sufficient toheat the catalyst to a temperature great enough to carry out theendothermic reactions in the reactor portion 200. Thus, the combustionfuel source may further include a supplemental fuel. The supplementalfuel may be part of the supplemental fuel stream 356, which may beintroduced to the combustor 350 through a supplemental fuel inlet 354.For example, the supplemental fuel stream 356 may be injected into thecombustor 350 through the supplemental fuel inlet 354 and thesupplemental fuel combusted to heat the catalyst to a temperaturesufficient to conduct the endothermic reactions in the reactor portion200 as well provide for the other heat demands in the entire reactorsystem 102. In some embodiments, no coke may be formed on the catalystsuch that all of the heat for raising the temperature of the catalyst isprovided by the supplemental fuel. In some embodiments, reactive gases,such as an oxygen-containing gas (e.g., air) or other oxidizer forexample, may be introduced to the combustor 350 through lower combustorinlet port 352 and may react with the supplemental fuel of thesupplemental fuel stream 356 to promote combustion of the supplementalfuel to heat the catalyst to produce the heated catalyst. As usedherein, the term “heated catalyst” refers to the catalyst after heatingthrough combustion of the supplemental fuel stream 356, the catalysthaving a temperature greater than the catalyst passed from the catalystseparation section 210 to the catalyst processing portion 300 of thereactor system 102.

Referring to FIG. 1, the processed catalyst may be passed out of thecombustor 350 and through the riser 330 to a riser termination separator378, where the gas and solid components from the riser 330 may be atleast partially separated. The vapor and remaining solids may betransported to a secondary separation device 320 in the catalystseparation section 310 where the remaining processed catalyst isseparated from the gases from the catalyst processing (e.g., gasesemitted by combustion of coke deposits and supplemental fuel). In someembodiments, the secondary separation device 320 may include one or aplurality of cyclone separation units, which may be arranged in seriesor in multiple cyclone pairs. The combustion gases from combustion ofcoke and/or the supplemental fuel during processing of the catalyst orother gases introduced to the catalyst during catalyst processing may beremoved from the catalyst processing portion 300 via a combustion gasoutlet 432.

As previously discussed, processing the catalyst in the catalystprocessing portion 300 of the reactor system 102 may includereactivating the catalyst. Combustion of the supplemental fuel in thepresence of the catalyst to heat the catalyst may further deactivate thecatalyst. Thus, in some embodiments, the catalyst may be reactivated byconditioning the catalyst through an oxygen treatment. The oxygentreatment to reactivate the catalyst may be conducted after combustionof the supplemental fuel to heat the catalyst. The oxygen treatment mayinclude treating the heated catalyst with an oxygen-containing gas for aperiod of at least two minutes, which may reactivate the catalyst toproduce a reactivated catalyst. The oxygen-containing gas may include anoxygen content of from 5 mole % to 100 mole % based on total molar flowrate of the oxygen-containing gas. In some embodiments, the catalyst maybe reactivated by conditioning the catalyst through an oxygen treatment.Oxygen treatment of the catalyst may include maintaining the catalyst ata temperature of at least 660° C. while exposing the catalyst to a flowof an oxygen-containing gas for a period of time greater than twominutes and sufficient to produce a reactivated catalyst having acatalytic activity that is greater than the heated catalyst after beingheated by combustion of the supplemental fuel.

Referring to FIG. 1, treatment of the heated catalyst with theoxygen-containing gas may be conducted in the oxygen treatment zone 370.In some embodiments, the oxygen treatment zone 370 may be downstream ofthe catalyst separation portion 310 of the catalyst processing portion300, such that the heated catalyst is separated from the combustiongases before being exposed to the oxygen-containing gas during theoxygen treatment. In some embodiments, the oxygen treatment zone 370 mayinclude a fluid solids contacting device. The fluid solids contactingdevice may include baffles or grid structures to facilitate contact ofthe heated catalyst with the oxygen-containing gas. Examples of fluidsolid contacting devices are described in further detail in U.S. Pat.Nos. 9,827,543 and 9,815,040, both of which are incorporated byreference herein in their entirety.

In some embodiments, processing the catalyst in the catalyst processingportion 300 of the reactor system 102 may further include stripping theoxygen-containing reactivated catalyst of molecular oxygen trappedwithin or between catalyst particles and physisorbed oxygen that isdesorbable at a temperature of at least 660° C. The stripping step mayinclude maintaining the oxygen-containing reactivated catalyst at atemperature of at least 660° C. and exposing the oxygen-containingreactivated catalyst to a stripping gas that is substantially free ofmolecular oxygen and combustible fuels for a period of time to removethe molecular oxygen from between particles and physisorbed oxygen thatis desorbable at the temperature of at least 660° C. Further descriptionof these catalyst reactivation processes are disclosed in U.S. Pat. No.9,834,496, which is incorporated by reference in the present disclosurein its entirety.

Following processing of the catalyst, the processed catalyst may bepassed from the catalyst processing portion 300 back into the reactorportion 200 via standpipe 424. For example, in some embodiments, theprocessed catalyst may be passed from the oxygen treatment zone 370 ofthe catalyst processing portion 300 to the upstream reactor section 250via standpipe 424 and transport riser 430, where the processed catalystmay be further utilized in a catalytic reaction. Thus, in operation, thecatalyst may cycle between the reactor portion 200 and the catalystprocessing portion 300. In general, the processed chemical streams,including the feed streams and product streams may be gaseous, and thecatalyst may be a fluidized particulate solid.

Referring again to FIG. 1, according to one or more embodiments,processing the catalyst in the catalyst processing portion 300 mayinclude passing the catalyst from the reactor portion 200 of the reactorsystem 102 to the combustor 350 of the catalyst processing portion 300,combusting the supplemental fuel in the combustor 350 to heat thecatalyst, subjecting the heated catalyst to an oxygen treatment in theoxygen treatment zone 370 to produce a reactivated catalyst, and passingthe reactivated catalyst from catalyst processing portion 300 to thereactor portion 200. Combustion of the supplemental fuel and/or cokedeposits in the catalyst processing portion 300 may remove the cokedeposits or other contaminants deposited on the catalyst, increase thetemperature of the catalyst to an operating temperature range of thereactor portion 200, or both. For example, in some embodiments,combustion of the supplemental fuel in the combustor 350 may increasethe temperature of the catalyst to produce a heated catalyst. In someembodiments, coke deposits may not be formed on the catalyst during thereaction, and the supplemental fuel may provide all of the heat in thecombustor for raising the temperature of the catalyst to produce theheated catalyst.

In some embodiments, the supplemental fuel may include hydrogen andother combustible fuels. A molar ratio of hydrogen to the othercombustible fuels in the supplemental fuel may be at least 1:1. Forexample, in some embodiments, the molar ratio of hydrogen to othercombustible fuels in the supplemental fuel may be greater than or equalto 7:3, greater than or equal to 4:1, or even greater than or equal to9:1. In some embodiments, the molar ratio of hydrogen to othercombustible fuels in the supplemental fuel may be from 1:1 to 999:1,from 1:1 to 99:1, from 1:1 to 49:1, from 1:1 to 19:1, from 1:1 to 9:1,from 7:3 to 999:1, from 7:3 to 99:1, from 7:3 to 49:1, from 7:3 to 19:1,from 7:3 to 9:1, from 4:1 to 999:1, from 4:1 to 99:1, from 4:1 to 49:1,from 4:1 to 19:1, or from 4:1 to 9:1.

In some embodiments, the supplemental fuel may include greater than orequal to 70 mol % hydrogen, such as greater than or equal to 75 mol %,greater than or equal to 80 mol %, greater than or equal to 85 mol %, orgreater than or equal to 90 mol % hydrogen, based on the total moles ofcombustible constituents in the supplemental fuel. Combustibleconstituents can include the hydrogen, hydrocarbons, and othercombustible fuels, or any other constituent that undergoes combustion attemperatures in the operating range of the combustor 350, but does notinclude constituents, such as inert gases (e.g., nitrogen, argon, etc.)and other constituents that do not combust at temperatures in theoperating range of the combustor 350. For example, in some embodiments,the supplemental fuel may include from 70 mol % to 100 mol %, from 70mol % to 99 mol %, from 70 mol % to 95 mol %, from 70 mol % to 90 mol %,from 70 mol % to 85 mol %, from 75 mol % to 100 mol %, from 75 mol % to99 mol %, from 75 mol % to 95 mol %, from 75 mol % to 90 mol %, from 75mol % to 85 mol %, from 80 mol % to 100 mol %, from 80 mol % to 99 mol%, from 80 mol % to 95 mol %, from 80 mol % to 90 mol %, from 85 mol %to 100 mol %, from 85 mol % to 99 mol %, from 85 mol % to 95 mol %, orfrom 90 mol % to 100 mol % hydrogen based on the total moles ofcombustible constituents in the supplemental fuel. The proportion ofhydrogen in the supplemental fuel may also be expressed as a weightpercent (wt. %). For example, in some embodiments, the supplemental fuelmay include greater than or equal to 20 wt. %, greater than or equal to25 wt. %, or greater than or equal to 30 wt. %, greater than or equal to40 wt. %, or greater than or equal to 50 wt. % hydrogen based on thetotal mass of combustible constituents in the supplemental fuel. Forexample, in some embodiments, the supplemental fuel may include from 20wt. % to 100 wt. %, from 20 wt. % to 99 wt. %, from 20 wt. % to 95 wt.%, from 25 wt. % to 100 wt. %, from 25 wt. % to 99 wt. %, from 25 wt. %to 95 wt. %, from 30 wt. % to 100 wt. %, from 30 wt. % to 99 wt. %, from30 wt. % to 95 wt. %, from 40 wt. % to 100 wt. %, from 40 wt. % to 99wt. %, from 40 wt. % to 95 wt. %, from 50 wt. % to 100 wt. %, or from 50wt. % to 99 wt. % hydrogen based on the total mass of combustibleconstituents in the supplemental fuel.

It was surprisingly found that heating the catalyst with a supplementalfuel having a relatively high concentration of hydrogen (e.g., molarratio of hydrogen to other combustible fuels of at least 1:1) canincrease the conversion of the reactor system compared to reactivatingthe catalyst with a supplemental fuel that consists of mainly methaneand other hydrocarbons (>50 mol % methane and/or other hydrocarbons).Incorporating a relatively high concentration of hydrogen into thesupplemental fuel in combination with the oxygen treatment to reactivatethe catalyst may result in a greater catalytic activity of thereactivated catalyst compared to catalyst heated by combustion of asupplemental fuel that consists of mainly methane and other hydrocarbonsin combination with the oxygen treatment. As previously discussed,combustion of the supplemental fuel that includes a relatively highconcentration of hydrogen to heat the catalyst in combination with theoxygen treatment may increase the lifetime of the catalyst in thereactor system 102. Further, combustion of the supplemental fuel havinga relatively high concentration of hydrogen in combination with theoxygen treatment may also increase the capacity of the reactor system102, such as by increasing the conversion for a specific catalystloading or reducing the catalyst loading required to achieve a targetconversion for example, compared to combusting a supplemental fuel witha high hydrocarbon concentration (>50 mol % hydrocarbon) to heat thecatalyst. For example, in a reactor system 102 utilizing a catalystcomprising platinum, gallium, or both to dehydrogenate propane toproduce propylene, operating the reactor system 102 utilizing asupplemental fuel having a molar ratio of hydrogen to other combustiblefuels of at least 1:1 can produce the same conversion performance withless active metal (e.g., platinum, gallium, or both) compared tooperating the reactor system with a supplemental fuel that is primarilymethane and other hydrocarbons (i.e., >50 mol % hydrocarbon). Operatingthe reactor system with less active metal (e.g., platinum, gallium, orboth) may include operating with a reduced bulk inventory of catalyst inthe reactor system or reducing the amount of the active metal in thecatalyst (e.g., using a catalyst having less active metal applied to thecatalyst or using aged catalyst).

In some embodiments, the supplemental fuel may include other combustiblefuels. Examples of other combustible fuels may include one or morehydrocarbons. The hydrocarbon may include a hydrocarbon or mixture ofhydrocarbons that comprises energy value upon combustion. In someembodiments, the hydrocarbons may include one or more hydrocarbons thatare gases at the operating temperatures of the combustor 350 (i.e., 650°C. to 850° C.), such as but not limited to, alkanes, alkenes, aromatichydrocarbons, or combinations of these. Examples of alkanes that may beincluded as a hydrocarbon in the supplemental fuel may include, but arenot limited to methane, ethane, propane, butane, isobutane, pentane,other alkanes, or combinations of these. Examples of alkenes (olefins)that may be included as a hydrocarbon of the supplemental fuel mayinclude, but are not limited to, ethylene, propylene, 1-butene,2-butene, isobutene, other olefins, or combinations of these. Examplesof aromatic hydrocarbons that may be included as a hydrocarbon in thesupplemental fuel may include, but are not limited to, benzene, toluene,xylene, other aromatic hydrocarbons, or combinations of these. In someembodiments, the hydrocarbons may include a light hydrocarbon (i.e.,C₁-C₄) fuel gas. In other embodiments, the hydrocarbons may includeheavy hydrocarbon based fuel oils (C₅₊). In some embodiments, thehydrocarbon in the supplemental fuel may include at least one ofmethane, ethane, propane, natural gas, other hydrocarbon fuel, orcombinations of these. Other combustible fuels other than hydrocarbonsmay also be included in the supplemental fuel.

In some embodiments, the supplemental fuel may include less than 30 mol% hydrocarbon based on the total moles of combustible constituents inthe supplemental fuel. For example, in some embodiments, thesupplemental fuel may include less than 25 mol %, less than 20 mol %,less than 15 mol %, or even less than 10 mol % hydrocarbon based on thetotal moles of combustible constituents in the supplemental fuel. Somehydrocarbon-based combustible fuels, such as methane and natural gas forexample, have a high heat value and are relatively inexpensive. Thus, insome embodiments, hydrocarbon fuels, such as methane and natural gas forexample, may be included in the supplemental fuel to reduce theoperating costs of the reactor system 102. In other embodiments, thehydrocarbons in the supplemental fuel may be provided by an off-gasstream passed to the combustor 350 as at least a portion of thesupplemental fuel stream 356, the off-gas stream originating from ahydrocarbon processing system. In some embodiments, the supplementalfuel stream 356 may include other non-combustible constituents. In someembodiments, the supplemental fuel stream 356 may include at least 10mol % combustible constituents based on the total moles of thesupplemental fuel. For example, the supplemental fuel stream 356 mayinclude at least 20 mol %, at least 30 mol %, at least 40 mol %, atleast 50 mol %, at least 70 mol %, at least 80 mol %, or at least 90 mol% combustible constituents based on the total moles of the supplementalfuel stream 356.

As previously discussed, the supplemental fuel stream 356 may includethe supplemental fuel comprising hydrogen and other combustible fuels.In some embodiments, the supplemental fuel stream 356 may include apurity hydrogen stream comprising greater than or equal to 99 mol %hydrogen based on the total molar flow rate of the purity hydrogenstream. In some embodiments, the supplemental fuel stream 356 mayinclude an off-gas stream from a hydrocarbon processing plant. Theoff-gas stream from a hydrocarbon processing plant/system may includegreater than or equal to 50 mol %, greater than or equal to 60 mol %,greater than or equal to 70 mol %, greater than or equal to 80 mol %, orgreater than or equal to 90 mol % hydrogen based on the total molar flowrate of combustible constituents in the off-gas stream. For example, insome embodiments, the supplemental fuel stream 356 may include anoff-gas stream from an FCDh reactor system, such as but not limited to apropane dehydrogenation process, and/or an off-gas stream from a lighthydrocarbon cracking process. It is understood that hydrogen-containingoff-gas streams from other hydrocarbon processing systems may beincluded in the supplemental fuel stream 356. In some embodiments, thesupplemental fuel stream 356 may consist of or consist essentially of anoff-gas stream from a hydrocarbon processing system. In otherembodiments, the supplemental fuel stream 356 may include the off-gasstream in combination with one or more other combustible fuel streamscomprising hydrogen, a hydrocarbon component, other combustible fuel, orcombinations of these. In some embodiments, the supplemental fuel stream356 may include one or more inert constituents as a diluent. Examples ofinert constituents may include inert gases such as nitrogen and argonfor example, or other constituents that do not combust at temperaturesin the operating range of the combustor 350.

Referring now to FIG. 2, a process flowchart of a fluidized catalyticdehydrogenation (FCDh) process 502 for dehydrogenating hydrocarbons toproduce olefins and other products (e.g., styrene from ethylbenzene). Inthe FCDh process 502 of FIG. 2, an off-gas stream 544 recovered from theFCDh process 502 may be passed to the combustor 350 to provide at leasta portion of the supplemental fuel stream 356. The FCDh process 502depicted in FIG. 2 may include the reactor system 102 depicted inFIG. 1. The FCDh process 502 may include the reactor 202, the catalystseparation section 210, the combustor 350, and the oxygen treatment zone370. The FCDh process 502 may further include a product separator 540downstream of the catalyst separation section 210.

During continuous operation of the FCDh process 502 of FIG. 2, achemical feed 512 and the reactivated catalyst 532 from the oxygentreatment zone 370 may be introduced to the reactor 202. Contact ofreactants in the chemical feed 512 with the reactivated catalyst 532 mayconvert a portion of reactants in the chemical feed 512 to one or morereaction products (e.g., ethylene, propylene, styrene, etc.) andby-products. A reactor effluent 514 may be passed from the reactor 202to the catalyst separation section 210. The reactor effluent 514 mayinclude at least catalyst, reaction products, and unreacted reactantsfrom the chemical feed, but may also include by-products, intermediatecompounds, impurities, carrier gases, or other constituents. Thecatalyst separation section 210 may separate the reactor effluent 514into a gaseous effluent stream 522 and a deactivated catalyst stream524. The gaseous effluent stream 522 may include at least reactionproducts and unreacted reactant gases. The deactivated catalyst stream524 may be passed to the combustor 350 for at least a portion of thecatalyst processing. In the combustor 350, the supplemental fuel stream356 may be combusted in the presence of the deactivated catalyst stream524 to remove coke from the catalyst, heat the catalyst, or both.Following combustion, the heated catalyst 531 may be separated from thecombustion gases 534 and passed to the oxygen treatment zone 370. In theoxygen treatment zone 370, the heated catalyst 531 may be treated withan oxygen-containing gas 533 to produce the reactivated catalyst 532.The reactivated catalyst 532 may then be passed back to the reactor 202.

Referring still to FIG. 2, the gaseous effluent stream 522 may be passedto the product separator 540, which may be operable to separate thegaseous effluent stream 522 into at least one product stream 542 and atleast one off-gas stream 544. The off-gas stream 544 recovered from theproduct separator 540 of the FCDh process 502 may include at least 40mol %, at least 70 mol %, at least 75 mol %, at least 80 mol %, at least85 mol %, or even at least 90 mol % hydrogen based on the total molarflow rate of combustible constituents in the off-gas stream 544. Theoff-gas stream 544 may also include methane, nitrogen, and/or otherconstituents. At least a portion of the off-gas stream 544 recoveredfrom the product separator 540 may be passed to the combustor 350 as atleast a portion of the supplemental fuel stream 356. In someembodiments, the off-gas stream 544 may be combined with a secondaryfuel stream 358 to produce the supplemental fuel stream 356. In someembodiments, the secondary fuel stream 358 may be a hydrogen-containingstream having a greater concentration of hydrogen than the off-gasstream 544. In other embodiments, the secondary fuel stream 358 may be ahydrocarbon stream comprising one or more hydrocarbons, such as methaneor natural gas for example. In some embodiments, the flow rate of thesecondary fuel stream 358, the flow rate of the off-gas stream 544, orboth may be increased or decreased to change the composition (e.g.,hydrogen concentration) of the supplemental fuel stream 356.

Referring now to FIG. 3, a process flowchart depicts an embodiment inwhich a cracker off-gas stream 628 from a light hydrocarbon crackingprocess 602 may be passed to the combustor 350 of the reactor system 102as at least a portion of the supplemental fuel stream 356. As previouslydiscussed, the reactor system 102 can include the reactor 202, thecatalyst separation section 210, the combustor 350, and the oxygentreatment zone 370. In continuous operation, a chemical feed 104 and areactivated catalyst 112 from the oxygen treatment zone 370 may beintroduced to the reactor 202, in which contact of the reactivatedcatalyst 112 with reactants in the chemical feed 104 may convert atleast a portion of reactants in the chemical feed 512 to one or morereaction products. A reactor effluent 106 may be passed from the reactor202 to the catalyst separation section 210, in which the reactoreffluent 106 may be separated into a gaseous effluent stream 108 and adeactivated catalyst stream 110. The gaseous effluent stream 108, whichmay include at least one reaction product, may be passed to one or moredownstream operations for further processing. The deactivated catalyststream 110 may be passed to the combustor 350 for at least a portion ofthe catalyst processing. In the combustor 350, the supplemental fuelstream 356 may be combusted in the presence of the deactivated catalyststream 110 to remove coke from the catalyst, heat the catalyst, or both.Following combustion, the heated catalyst 111 may be separated from thecombustion gases 534 and passed from the combustor 350 to the oxygentreatment zone 370. In the oxygen treatment zone 370, the heatedcatalyst 111 may be treated with an oxygen-containing gas 533 to producethe reactivated catalyst 112. The reactivated catalyst 112 may then bepassed back to the reactor 202.

Referring still to FIG. 3, the light hydrocarbon cracking process 602may include a light hydrocarbon cracking unit 610 and a lighthydrocarbon processing portion 620. During continuous operation of thelight hydrocarbon cracking process 602, one or a plurality of lighthydrocarbon streams 612 may be introduced to the light hydrocarboncracking unit 610, in which light hydrocarbons in the hydrocarbonstreams 612 are cracked to produce a cracker effluent 614 that includesone or more reaction products. For example, in some embodiments, thelight hydrocarbon cracking unit 610 may be a steam cracker and the lighthydrocarbon streams 612 may include ethane and propane, which may besteam cracked in the steam cracker to produce at least ethylene. Thecracker effluent 614 may be passed to the light hydrocarbon processingportion 620 of the light hydrocarbon cracking process 602. The lighthydrocarbon processing portion 620 may include a plurality of unitoperations, such as but not limited to vapor compression, separation,sulfur and carbon dioxide removal, drying, or other operations. Thelight hydrocarbon processing portion 620 may ultimately separate thecracker effluent 614 into a plurality of gaseous streams, such as butnot limited to, an ethylene product stream 622, a propylene productstream 624, a propane stream 626, a cracker off-gas stream 628, andother streams.

The cracker off-gas stream 628 may include at least 40 mol % hydrogen,such as from 50 mol % to 90 mol % hydrogen based on the total molar flowrate of combustible constituents in the cracker off-gas stream 628. Atleast a portion of the cracker off-gas stream 628 may be passed to thecombustor 350 of the reactor system 102 to be included as a portion ofthe supplemental fuel stream 356. For example, in some embodiments, thecracker off-gas stream 628 may be passed directly to the combustor 350of the reactor system 102 as the supplemental fuel stream 356 so thatthe supplemental fuel stream 356 consists of or consists essentially ofthe cracker off-gas stream 628. In some embodiments, the cracker off-gasstream 628 may be combined with a secondary fuel stream 358 to producethe supplemental fuel stream 356. The secondary fuel stream 358 may be ahydrogen-containing stream having a greater concentration of hydrogenthan the cracker off-gas stream 628. Alternatively, in some embodiments,the secondary fuel stream 358 may be a hydrocarbon stream comprising oneor more hydrocarbons. In some embodiments, the flow rate of thesecondary fuel stream 358, the flow rate of the cracker off-gas stream628, or both may be increased or decreased to modify the composition(e.g., hydrogen concentration) of the supplemental fuel stream 356.

In some embodiments, at least a portion of the cracker off-gas stream628 may be combined with an off-gas stream from the reactor system 102(e.g., off-gas stream 544 from the FCDh process 502 of FIG. 2) toproduce the supplemental fuel stream 356. The supplemental fuel stream356 may include off-gas streams from other hydrocarbon processes. Insome embodiments, the supplemental fuel stream 356 may include at leastone of an off-gas from an FCDh process, a cracker off-gas from a lighthydrocarbon cracking unit, a purity hydrogen stream, or combinations ofthese.

In some embodiments, the reactor system 102 and the light hydrocarboncracking process 602 may be integrated together to combine separation ofthe product streams into a single system. For example, in someembodiments, the gaseous effluent stream 108 from the reactor system 102may be combined with the cracker effluent 614 from the light hydrocarboncracking unit 610, and the combined effluent stream (not shown) may bepassed to the light hydrocarbon processing portion 620. Thus, in theseembodiments, the light hydrocarbon processing portion 620 may separatethe combined effluent stream (e.g., the combination of both the gaseouseffluent stream 108 and cracker effluent 614) into a plurality ofgaseous streams, such as but not limited to, the ethylene product stream622, the propylene product stream 624, the propane stream 626, thecracker off-gas stream 628, and other streams. In particular, in someembodiments, the gaseous effluent stream 522 (FIG. 2) from the FCDhprocess 502 (FIG. 2) may be combined with the cracker effluent 614 ofthe light hydrocarbon cracking process and may be passed therewith tothe light hydrocarbon processing portion 620 of the light hydrocarboncracking process 602 so that the cracker off-gas stream 628 includesoff-gases produced from the light hydrocarbon cracking unit 610 and theFCDh process 502 (FIG. 2).

Referring to FIG. 4, in some embodiments, the cracker off-gas stream 628may be passed to a separator device 630, such as a turbo expander orother separation device. The separator device 630 may be operable toseparate the cracker off-gas stream 628 into a hydrogen-rich stream 362and a hydrocarbon-rich stream 360. The hydrogen-rich stream 362 may bepassed from the separator device 630 to the combustor 350 of the reactorsystem 102 as at least a portion of the supplemental fuel stream 356.The supplemental fuel stream 356 may include the hydrogen-rich stream362 from the separator device 630. Off-gas streams from otherhydrocarbon processing systems (e.g., off-gas stream 544 from the FCDhprocess 502 of FIG. 2) may also be passed to a separator device 630 toproduce a hydrogen-rich stream and a hydrocarbon-rich stream and thenpassing at least the hydrogen-rich stream to the combustor 350 of thereactor system 102 as a part of the supplemental fuel stream 356. Insome embodiments, the operating parameters of the separator device 630may be modified to increase or decrease a concentration of hydrogen inthe hydrogen-rich stream 362 to thereby increase or decrease theconcentration of hydrogen in the supplemental fuel stream 356.

In some embodiments, the hydrogen concentration of the supplemental fuelstream 356 may be modified by removing at least a portion of thehydrocarbon component from the supplemental fuel stream 356.Additionally, in some embodiments, the hydrogen concentration of thesupplemental fuel stream 356 may be modified by combining thesupplemental fuel stream 356 with a supplemental hydrogen-containingstream, a supplemental hydrocarbon stream, or both.

During continuous reaction phase of operation of the reactor system 102,the catalyst processing portion 300 of the reactor system 102, inparticular the combustor 350, may be maintained at a temperature in anoperating temperature range sufficient to reactivate the catalyst. Forexample, in some embodiments, the combustor 350 may be maintained at atemperature greater than the operating temperature of the reactorportion 200 of the reactor system 102. In some embodiments, theoperating temperature range of the combustor 350 may be greater than orequal to 650° C., greater than or equal to 660° C., even greater than orequal to 680° C., or even greater than or equal to 700° C. In someembodiments, the operating temperature range of the combustor 350 may befrom 650° C. to 850° C., from 660° C. to 780° C., or from 700° C. to750° C. As previous discussed herein, maintaining the operatingtemperature in the combustor 350 may include combusting a supplementalfuel in the combustor 350. As previous discussed herein, maintaining theoperating temperature in the combustor 350 may include combusting asupplemental fuel in the combustor 350.

Referring again to FIG. 1, the supplemental fuel stream 356 may beintroduced to the combustor 350 of the catalyst processing portion 300.In some embodiments, the supplemental fuel stream 356 may be introducedto the combustor 350 through one or more distributors (not shown)disposed within the combustor 350. Before introducing the supplementalfuel stream 356 to the combustor 350, the supplemental fuel stream 356may be passed through a compressor (not shown) to increase the pressureof the supplemental fuel stream 356. The supplemental fuel stream 356can be supplied to the combustor 350 at a pressure of from 5 pounds persquare inch gauge (psig) to 200 psig (from 34.47 kilopascals (kPa) to1378.95 kPa, where 1 psig=6.89 kPa). In some embodiments, a controlvalve (not shown) may be included to control the flow rate of thesupplemental fuel stream 356 and adjust the pressure of the supplementalfuel gas to equal the operating pressure of the reactor system 102and/or the combustor 350. In some embodiments, the supplemental fuelstream 356 may be preheated, such as by passing the supplemental fuelstream 356 through an optional heat exchanger (not shown).

According to one or more embodiments, the reaction in the reactor system102 may be an FCDh reaction system for dehydrogenating paraffins andalkyl aromatics to olefins or other products. According to suchembodiments, the feed stream may comprise paraffinic compounds such asone or more of ethane, propane, n-butane, i-butane. In some embodiments,the feed stream may include at least 50 wt. % ethane, propane, n-butane,i-butane, or combinations thereof. In one or more embodiments, adehydrogenation reaction may utilize a catalyst that includes platinum,gallium, or combinations thereof. The platinum and/or gallium may becarried by an alumina or alumina silica support, and may optionallycomprise potassium. Such platinum catalysts are disclosed in U.S. Pat.No. 8,669,406, which is incorporated herein by reference in itsentirety. In some embodiments, the reactor system 102 may be an FCDhreaction system for dehydrogenating alkyl aromatic compounds to otherproducts. For example, the feed stream may include ethylbenzene and thereactor system 102 may be an FCDh reactor system for dehydrogenating theethylbenzene to styrene.

In some embodiments, the reaction in the reactor system 102 may be acracking reaction such that the reactor system 102 is a cracking reactorsystem. According to such embodiments, the feed stream may comprise oneor more of naphtha, n-butane, or i-butane. For example, if the reactionis a cracking reaction, the feed stream may include at least 50 wt. %naphtha, n-butane, i-butane, or combinations thereof. In one or moreembodiments, a cracking reaction may utilize one or more zeolites as acatalyst. In some embodiments, the one or more zeolites utilized in thecracking reaction may comprise a ZSM-5 zeolite. However, it should beunderstood that other suitable catalysts may be utilized to perform thecracking reaction. In some embodiments, the cracking catalyst mayinclude platinum. For example, the cracking catalyst may include from0.001 wt. % to 0.05 wt. % of platinum. The platinum may be sprayed on asa soluble platinum compound, such as but not limited to platinumnitrate, platinum tetraamine nitrate, platinum acetylacetonate, orcombinations of these, and calcined at an elevated temperature, such asaround 700° C.

EXAMPLES

Embodiments of the present disclosure will be further clarified by thefollowing examples.

Example 1: Propane Dehydrogenation—Effects of Hydrogen Content ofSupplemental Fuel on Propane Conversion

In Example 1, the effects of the concentration of hydrogen in thesupplemental fuel stream on the conversion of propane in the propanedehydrogenation reactor system were evaluated. The propanedehydrogenation reactions were conducted using a Davidson CirculatingRiser (DCR) pilot plant unit obtained from Grace Davidson and having anupflow fluidized reactor portion and a catalyst processing portion. TheDCR unit was modified to allow in-situ fuel combustion in the catalystprocessing portion. Each reaction run 1A-1D was conducted with 4100grams of freshly loaded catalyst comprising platinum and galliumsupported on an alumina-containing silica carrier. The inlet temperatureto the riser reactor of the DCR unit was controlled at 630° C. and thepressure was set to 13 psig. The propane feed was an HD-5 propane feedwith around 30 parts per million (ppm) sulfur on a molar basis. Thepropane feed was diluted in nitrogen so that the partial pressure ofpropane in the feed stream was about 4.3 psig.

The temperature for catalyst processing was maintained in a range offrom 700° C. to 750° C. Catalyst processing included combustion of asupplemental fuel stream followed by an oxygen treatment in which thecatalyst was exposed to an oxygen-containing gas (air) for an oxygensoak time. The propane dehydrogenation reactions were conducted usingsupplemental fuel streams comprising various compositions of hydrogenand methane for the catalyst reactivation. For reaction runs 1A-1D, themolar concentration of hydrogen in the supplemental fuel stream wasincreased from 0 mol % hydrogen to 100 mol % hydrogen to change themolar ratio of hydrogen to methane in the supplemental fuel. The propanedehydrogenation reactions were conducted at constant heat input of about1,600 BTU/hour (1.6 KBTU/hr). For each reaction run, the DCR unit wasoperated for a first period with an oxygen soak time of 1 minute and fora second period with an oxygen soak time of 7 minutes.

The propane feed rate (standard liters per hour (SLPH)), catalystcirculation rate (kg/hr), supplemental fuel stream composition (mol %and wt. %), supplemental fuel stream feed rate (SLPH), heat input(MBTU/hr), ratio of catalyst to methane (lbs/lbs) in the catalystprocessing portion, propane weight hourly space velocity (WHSV hr⁻¹),and oxygen soak time of the oxygen treatment are provided below inTable 1. The propane conversions for operation of the reactor systemwith oxygen soak times of 1 minute and 7 minutes were determined andreported in Table 1.

TABLE 1 Example 1 Process Parameters and Propane Conversion Reaction Run1A 1B 1C 1D Supplemental Fuel Composition Methane Concentration (mol %)100 75 20 0 Hydrogen Concentration (mol %) 0 25 80 100 Molar RatioH₂:CH₄ 0:100 1:3 4:1 100:0 Methane Content (wt. %) 100 96 67 0 HydrogenContent (wt. %) 0 4 33 100 Reaction Process Parameters Propane Feed Rate(SLPH) 180 180 180 180 Propane WHSV (hr⁻¹) 4.5 4.4 3.6 3.7 CatalystCirculation Rate (kg/hr) 18.6 19.5 20.2 19.5 Supplemental Fuel Rate(SLPH) 50 61 113 164 Heat Input (KBTU/hr) 1.57 1.58 1.56 1.54 PropaneConversion Propane Conversion (%)-oxygen 42.1 42.9 45.7 48.2 soak timeof 1 minute Propane Conversion (%)-oxygen 43.2 43.9 45.8 49.1 soak timeof 7 minutes

As shown in Table 1, for Example 1, when the molar concentration ofhydrogen in the supplemental fuel is increased from 0 mol % to 100 mol %(increasing the molar ratio of hydrogen to methane in the supplementalfuel from 0:100 to 100:0), the propane conversion with an oxygen soaktime of 1 minute is observed to increase from 42.1% to 48.2%. Thus,increasing the concentration of hydrogen in the supplemental fuel streamfrom 0 mol % to 100 mol % increased the propane conversion by 14.5%.

Example 2: Propane Dehydrogenation—Effect of Hydrogen Content ofSupplemental Fuel on Propane Conversion at High Heat Input

In Example 2, the effects of hydrogen concentration of the supplementalfuel stream on propane conversion in a propane dehydrogenation reactorsystem operating at high heat input were valuated. The propanedehydrogenation reactions were conducted in the DCR unit described inExample 1. In Example 2, the catalyst processing was conducted at highheat input which was accomplished by increasing the supplemental fuelstream flow rate to 3 times the supplemental fuel stream flow rate ofExample 1. The propane dehydrogenation reactions were conducted atconstant heat input of about 4,700 BTU/hour (4.7 KBTU/hr). All otheroperating parameters were the same. The propane dehydrogenationreactions were conducted using supplemental fuel streams comprisinghydrogen and methane. For reaction runs 2A-2D, the molar concentrationof hydrogen in the supplemental fuel stream was increased from 0 mol %hydrogen to 100 mol % hydrogen. The propane feed rate, catalystcirculation rate, supplemental fuel stream composition, supplementalfuel stream feed rate, heat input, ratio of catalyst to methane in thecatalyst processing portion of the reaction system, propane WHSV, andoxygen soak time of the oxygen treatment are provided below in Table 2.The propane conversions for operation of the reactor system with oxygensoak times of 1 minute and 7 minutes were determined and reported inTable 1.

TABLE 2 Example 2 Process Parameters and Propane Conversion Reaction Run2A 2B 2C 2D Supplemental Fuel Composition Methane Concentration (mol %)100 75 20 0 Hydrogen Concentration (mol %) 0 25 80 100 Molar RatioH₂:CH₄ 0:100 1:3 4:1 100:0 Methane Content (wt. %) 100 96 67 0 HydrogenContent (wt. %) 0 4 33 100 Reaction Process Parameters Propane Feed Rate(SLPH) 180 180 180 180 Propane WHSV (hr⁻¹) 5.4 3.7 3.2 3.8 CatalystCirculation Rate (kg/hr) 18.0 20.0 20.2 20.1 Supplemental Fuel Rate(SLPH) 150 182 338 394.3 Heat Input (KBTU/hr) 4.71 4.72 4.67 3.71Propane Conversion Propane Conversion (%)-oxygen 34.9 37.2 44.0 48.5soak time of 1 minute Propane Conversion (%)-oxygen 37.7 43.1 47.0 49.1soak time of 7 minutes

As shown in Table 2, for Example 2, when the molar concentration ofhydrogen in the supplemental fuel is increased from 0 mol % to 100 mol %(increase the molar ratio of hydrogen to methane in the supplementalfuel from 0:100 to 100:0), the propane conversion with an oxygen soaktime of 1 minute is observed to increase from 34.9% to 48.5%. At highheat input (3 times the supplemental fuel stream feed rate of Example1), the increase in propane conversion in Example 2 was 39% byincreasing the hydrogen concentration in the supplemental fuel from 0mol % to 100 mol %. Thus, at high heat input, increasing the hydrogenconcentration in the supplemental fuel stream results in a greaterincrease in the propane conversion compared to Example 1, for which theheat input was less.

Referring to FIG. 5, propane conversion (%) (y-axis) as a function ofthe hydrogen concentration (wt. %) in the supplemental fuel stream(x-axis) is provided for the propane dehydrogenation reactions ofExample 1 (902) and Example 2 (904) with an oxygen soak time of 1minutes. As shown graphically in FIG. 5, the propane conversionincreases as the concentration of hydrogen in the supplemental fuelincreases given that the total heat input to the reactor system is heldconstant. The increase in propane conversion is more gradual forhydrogen concentrations in the supplemental fuel of from 0 mol % toabout 50 mol %. When the concentration of hydrogen in the supplementalfuel is increased to greater than 50 mol %, the rate at which thepropane conversion increases with increasing concentration of hydrogenin the supplemental fuel become more rapid. This indicates asupplemental fuel that contains at least 50 mol % hydrogen (i.e., amolar ratio of hydrogen to other combustible fuels of at least 1:1)provides a considerable improvement in the propane conversion comparedto a supplemental fuels having a molar ratio of hydrogen to othercombustible fuels of less than 1:1. The same trend of propane conversionas a function of hydrogen concentration in the supplemental fuel streamis observed when the oxygen soak time is increased to 7 minutes.

FIG. 5 also graphically shows that the effect of the hydrogenconcentration in the supplemental fuel stream on propane conversion isgreater for operation at high heat input (Example 2 (904)) compared tothe propane conversion for operation at lower heat input (Example 1(902)).

Example 3: Lab Scale Propane Dehydrogenation—Effects of HydrogenConcentration in the Supplemental Fuel Stream

In Example 3, the effects of changing the hydrogen concentration in thesupplemental fuel stream on the propane conversion was further studiedusing a lab scale propane dehydrogenation reactor system. The propanedehydrogenation reactions of Example 3 were conducted using a lab scalefixed bed testing rig containing the same catalyst previously describedin Example 1. The fixed bed reactor system was alternated betweenpropane dehydrogenation operation and catalyst reactivation to simulatereaction/catalyst processing cycles.

During propane dehydrogenation reaction operation, a feed streamcomprising 90 mol % propane and 10 mol % nitrogen was introduced to thefixed bed reactor at a propane weight hourly space velocity (WHSV) of 10hr⁻¹. The propane dehydrogenation reactions were conducted at a reactiontemperature of 625° C. at ambient pressure. Each reaction step of thedehydrogenation/catalyst processing cycles in Example 3 was conductedfor a total on-stream-time of 60 seconds, with the propane conversionand selectivity data measured 30 seconds after introducing the feedstream to the fixed bed reactor.

During each catalyst processing step of the dehydrogenation/catalystprocessing cycles, a combustion gas mixture comprising a supplementalfuel stream and air was introduced to the fixed bed reactor at 730° C.for 3 minutes. The combustion gas mixture included 2.5 mol % of thesupplemental fuel stream and the balance of the combustion gas mixturewas air. The composition of the supplemental fuel stream consisted ofmethane (CH₄) and hydrogen (H₂), and the concentration of hydrogen inthe supplemental fuel stream was increased from 0 wt. % to 100 wt. % inreaction runs 3A-3F. Following combustion for 3 minutes, the catalyst inthe fixed bed was subjected to air treatment with high purity air (>99%air) at 730° C. for 15 minutes.

Table 3 provides propane conversion and propylene selectivity for thepropane dehydrogenation reactions conducted in reaction runs 3A-3F. Thepropane conversion and propane selectivity in Table 3 for each ofreaction runs 3A-3F were determined after the performance reached steadystate (typically 20-25 reaction/catalyst processing cycles under thedesignated conditions in the reactor system).

TABLE 3 Propane Conversion and Propylene Selectivity for PropaneDehydrogenations of Example 3 Supplemental Fuel Stream CompositionPropane Propylene Rxn CH₄ H₂ Molar Ratio Conversion Selectivity Run (mol%) (mol %) H₂:CH₄ (%) (mol %) 3A 100 0  0:100 48.2 96.4 3B 75 25  1:348.8 96.5 3C 50 50  1:1 50.0 96.6 3D 20 80  4:1 50.9 96.6 3E 10 90  9:151.2 96.6 3F 0 100 100:0 53.1 96.8

As shown above in Table 3, for Example 3, when the concentration ofhydrogen in the supplemental fuel was increased from 0 mol % to 100 mol% (increase in the molar ratio of hydrogen to methane in thesupplemental fuel from 0:100 to 100:0), the propane conversion wasobserved to increase from 48.2% to 53.1%. Thus, increasing theconcentration of hydrogen in the supplemental fuel stream from 0 mol %to 100 mol % increased the propane conversion by 10.2% for the lab scalereactor process of Example 3. Increasing the hydrogen concentration from0 mol % to 100 mol % also increased the propylene selectivity from 96.4mol % to 96.8 mol %.

Referring to FIG. 6, propane conversion 910 (y-axis left) and propyleneselectivity 912 (y-axis right) as functions of the concentration ofhydrogen in the supplemental fuel stream (x-axis) are graphicallydepicted. As shown graphically in FIG. 6, the propane conversion 910 andpropylene selectivity 912 both increase as the concentration of hydrogenin the supplemental fuel stream increases. FIG. 6 also shows that theincrease in propane conversion 910 is generally linear for hydrogenconcentrations in the supplemental fuel of from 0 mol % to about 70 mol%. However, when the concentration of hydrogen in the supplemental fuelstream increases above about 70 mol %, the propane conversion 910increases more rapidly compared to the generally linear increase inpropane conversion at hydrogen concentrations of from 0 mol % to about70 mol % hydrogen in the supplemental fuel. This indicates asupplemental fuel stream that contains at least 70 mol % hydrogenprovides greater improvement in the propane conversion compared tosupplemental fuel streams having less than 70 mol % hydrogen.

For the purposes of describing and defining the present invention it isnoted that the term “about” is utilized herein to represent the inherentdegree of uncertainty that may be attributed to any quantitativecomparison, value, measurement, or other representation. The term isalso utilized herein to represent the degree by which a quantitativerepresentation may vary from a stated reference without resulting in achange in the basic function of the subject matter at issue.

It is noted that one or more of the following claims utilize the term“wherein” as a transitional phrase. For the purposes of defining thepresent invention, it is noted that this term is introduced in theclaims as an open-ended transitional phrase that is used to introduce arecitation of a series of characteristics of the structure and should beinterpreted in like manner as the more commonly used open-ended preambleterm “comprising.”

Generally, “inlet ports” and “outlet ports” of any system unit of thereactor system 102 described herein refer to openings, holes, channels,apertures, gaps, or other like mechanical features in the system unit.For example, inlet ports allow for the entrance of materials to theparticular system unit and outlet ports allow for the exit of materialsfrom the particular system unit. Generally, an outlet port or inlet portwill define the area of a system unit of the reactor system 102 to whicha pipe, conduit, tube, hose, material transport line, or like mechanicalfeature is attached, or to a portion of the system unit to which anothersystem unit is directly attached. While inlet ports and outlet ports maysometimes be described herein functionally in operation, they may havesimilar or identical physical characteristics, and their respectivefunctions in an operational system should not be construed as limitingon their physical structures.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the present inventionwithout departing from the spirit and scope of the invention. Sincemodifications combinations, sub-combinations and variations of thedisclosed embodiments incorporating the spirit and substance of theinvention may occur to persons skilled in the art, the invention shouldbe construed to include everything within the scope of the appendedclaims and their equivalents.

The invention claimed is:
 1. A method for processing a chemical stream,the method comprising: contacting a feed stream with a catalyst in areactor portion of a reactor system, wherein: the reactor systemcomprises a reactor portion and a catalyst processing portion; thecatalyst comprises platinum, gallium, or both; and the contacting of thefeed stream with the catalyst causes a reaction which forms an effluentstream comprising at least one product; separating at least a portion ofthe effluent stream from the catalyst; passing the catalyst to thecatalyst processing portion of the reactor system; processing thecatalyst in the catalyst processing portion of the reactor system,wherein processing the catalyst comprises: passing the catalyst to acombustor of the catalyst processing portion; combusting a supplementalfuel in the combustor in the presence of the catalyst to produce aheated catalyst, wherein the supplemental fuel comprises hydrogen andother combustible fuels, and a molar ratio of hydrogen to the othercombustible fuels in the supplemental fuel is at least 1:1; treating theheated catalyst with an oxygen-containing gas to produce a reactivatedcatalyst; and passing the reactivated catalyst from the catalystprocessing portion to the reactor portion.
 2. A method fordehydrogenating a hydrocarbon stream to produce one or more olefins, themethod comprising: contacting a hydrocarbon feed stream with a catalystin a reactor portion of a reactor system, wherein: the reactor systemcomprises a reactor portion and a catalyst processing portion; thecatalyst comprises platinum, gallium, or both; and the contacting of thefeed stream with the catalyst causes a reaction which forms an effluentstream comprising the one or more olefins; separating at least a portionof the effluent stream from the catalyst; passing the catalyst to thecatalyst processing portion of the reactor system; processing thecatalyst in the catalyst processing portion of the reactor system,wherein processing the catalyst comprises: passing the catalyst to acombustor of the catalyst processing portion; introducing a supplementalfuel to the combustor, the supplemental fuel stream comprising hydrogenand at least one hydrocarbon, and a molar ratio of hydrogen to othercombustible fuels in the supplemental fuel is at least 1:1; combustingthe supplemental fuel in the combustor in the presence of the catalyst;subjecting a heated catalyst to an oxygen treatment to produce areactivated catalyst; and passing the reactivated catalyst from thecatalyst processing portion to the reactor portion.
 3. The method ofclaim 1, wherein the supplemental fuel further comprises at least onehydrocarbon.
 4. The method of claim 3, wherein the at least onehydrocarbon is chosen from methane, ethane, propane, n-butane,isobutane, ethylene, propylene, 1-butene, 2-butene, isobutene, pentene,benzene, toluene, xylene, natural gas, or combinations thereof.
 5. Themethod of claim 3, wherein the at least one hydrocarbon comprisesmethane.
 6. The method of claim 1, wherein a molar ratio of hydrogen toother combustible fuels in the supplemental fuel is from 1:1 to 99:1. 7.The method of claim 1, wherein treating the heated catalyst with theoxygen-containing gas comprises exposing the heated catalyst to theoxygen-containing gas for a time period of greater than 2 minutes. 8.The method of claim 1, further comprising passing a hydrogen-containingoff-gas stream from a hydrocarbon processing system to the combustor,wherein at least a portion of a supplemental fuel stream introduced tothe combustor comprises the hydrogen-containing off-gas stream.
 9. Themethod of claim 8, further comprising increasing the concentration ofhydrogen in the hydrogen-containing off-gas stream.
 10. The method ofclaim 1, wherein the supplemental fuel comprises at least a portion ofan off-gas stream from a light hydrocarbon cracking process or adehydrogenation process.
 11. The method of claim 1, further comprising:separating the effluent stream into a product stream and an off-gasstream; and passing at least a portion of the off-gas stream to thecatalyst processing portion, wherein the supplemental fuel includes theat least a portion of the off-gas stream.
 12. The method of claim 1,wherein the catalyst comprises platinum, gallium, and optionally analkali metal or alkaline earth metal supported on a carrier, the carrierchosen from one or more of silica, alumina, alumina-containing silica,TiO₂, ZrO₂, or combinations thereof.
 13. The method of claim 1, whereinthe reactor system comprises a dehydrogenation reaction system.
 14. Themethod of claim 1, wherein the product in the effluent stream comprisesat least one light olefin chosen from ethylene, propylene, or butene.15. The method of claim 1, further comprising operating the combustor ata temperature of from 650° C. to 850° C.
 16. The method of claim 2,wherein: the supplemental fuel further comprises at least onehydrocarbon; and the at least one hydrocarbon is chosen from methane,ethane, propane, n-butane, isobutane, ethylene, propylene, 1-butene,2-butene, isobutene, pentene, benzene, toluene, xylene, natural gas, orcombinations thereof.
 17. The method of claim 2, wherein a molar ratioof hydrogen to other combustible fuels in the supplemental fuel is from1:1 to 99:1.
 18. The method of claim 2, wherein the supplemental fuelcomprises at least a portion of an off-gas stream from a lighthydrocarbon cracking process or a dehydrogenation process.
 19. Themethod of claim 2, further comprising: separating the effluent streaminto a product stream and an off-gas stream; and passing at least aportion of the off-gas stream to the catalyst processing portion,wherein the supplemental fuel includes the at least a portion of theoff-gas stream.
 20. The method of claim 2, wherein the catalystcomprises platinum, gallium, and optionally an alkali metal or alkalineearth metal supported on a carrier, the carrier chosen from one or moreof silica, alumina, alumina-containing silica, TiO₂, ZrO₂, orcombinations thereof.